1. Field of the Invention
The present invention relates to a method and apparatus for emission lithography using a patterned emitter.
2. Description of the Related Art
An apparatus for performing ferroelectric switching lithography, which uses a patterned emitter, emits electrons by switching a patterned ferroelectric emitter to expose an electron resist on a substrate to form a desired pattern which is the same as that of the emitter. Ferroelectric switching emission is disadvantageous in that the electrode formed on the emitter by a mask absorbs electrons. Moreover, the emitter cannot reliably emit electrons when it is not connected to the electrode.
To solve the above problem, a feature of an embodiment of the present invention includes an apparatus for and method of emission lithography using a patterned emitter, in which a pyroelectric emitter or a ferroelectric emitter emits electrons when heated in a vacuum by infrared rays, a laser, or a heater. The emitter is patterned by a mask so that electrons emitted from the emitter expose an electron resist on a substrate to form a pattern which is the same as that of the emitter.
An apparatus for emission lithography according to an embodiment of the present invention comprises a plate type emitter separated from a substrate holder by a predetermined distance, the plate type emitter having a desired pattern on its surface facing the substrate holder and being formed of a pyroelectric or ferroelectric material; a heating source for heating the plate type emitter; and magnets or DC magnetic field generators disposed outside the emitter and the substrate holder, for controlling the path of electrons emitted from the plate type emitter.
Preferably, the heating source is a remote controlled heater which generates infrared rays or a laser, or a contact heating plate which uses resistance heating. The heating source is formed to heat the emitter to a phase transition temperature or higher.
There is also provided a method of providing a one-to-one projection of emission lithography comprising exposing a substrate to an emitter having a desired pattern on its surface facing a substrate holder; applying a voltage between the emitter and the substrate to allow electrons to be emitted along a path from the emitter and applied to the substrate; controlling the path of electrons using magnets or DC magnetic field generators disposed outside the emitter and the substrate holder; and heating the emitter.
Further, there is also provided an apparatus for an x-to-one projection of emission lithography, which comprises a plate type emitter separated from a substrate holder by a predetermined distance, the plate type emitter having a desired pattern on its surface facing the substrate holder and being formed of a pyroelectric or ferroelectric material; a heating source for heating the plate type emitter; and a deflection system disposed between the emitter and the substrate holder, for controlling the path of electrons emitted from the plate type emitter.
Preferably, the heating source is a remote controlled heater that generates infrared rays or a laser, or a contact heating plate which uses resistance heating. The heating source generates sufficient heat to heat the emitter to a phase transition temperature or higher. The deflection system includes deflectors for deflecting electrons emitted from the emitter; a magnetic lens disposed between the deflectors where the magnetic lens focuses the emitted electrons; and a diaphragm having an aperture for passing electrons focused by the magnetic lens and filtering out electrons drifting away from the focused electrons.
In addition, there is provided a method of providing an x-to-one projection of emission lithography comprising exposing a substrate to an emitter having a desired pattern on its surface facing a substrate holder; applying a voltage between the emitter and the substrate to allow electrons to be emitted along a path from the emitter and applied to the substrate; controlling the path of electrons emitted from an emitter structure toward an object to be etched, using a deflection system; and heating the emitter.
The invention, though, is pointed out with particularity by the appended claims.